In vitro screening and QTL analysis for drought tolerance in diploid potato

Abstract

Drought stress is a major abiotic constraint limiting crop production worldwide. Screening for drought tolerance and the traits that enhance drought tolerance is not straightforward in large mapping populations. In this study, we investigated the possibility of screening a mapping population in vitro for PEG-induced water deficit stress and recovery potential. We have measured several shoot and root growth parameters or traits in the C 9 E diploid potato mapping population. Significant variation was observed for genotype-specific responses to water deficit and recovery potential. Genetic variation and heritability estimates were high to very high for the measured traits depending on growth conditions. In order to identify potato QTLs for drought tolerance and recovery potential an SNP marker-rich integrated linkage map was used. A total of 23 QTLs were detected under control, stress and recovery treatments explaining 10.3-22.4% of the variance for each phenotypic trait. Among these, 10 QTLs were located on chromosome 2. Three QTLs involved in the important trait root to shoot ratio were identified on linkage groups 2, 3 and 8. These loci explained together 41.1% of the variance for this trait, and may be breeding targets for stress tolerance and yield in the field as well. The SNP markers derived from EST sequences underlying these QTLs led to the identification of putative candidate genes for further study in potato. This study constitutes the first knowledge of in vitro screening of a mapping population for drought tolerance in potato.

Genomewide identification of genes involved in the potato response to drought indicates functional evolutionary conservation with Arabidopsis plants

“…These potato cultivars differ in their bulking time, growth rate and sensitivity to pathogens and various abiotic stresses. Many classical and molecular studies have been performed to identify the genetic loci responsible for agricultural traits using diploid potato plants (Anithakumari et al ., , ; Gebhardt, ; Khan et al ., ; Mani and Hannachi, ). Recently, due to the development of high‐throughput RNA sequencing techniques, which enable qualitative and quantitative global analyses of gene expression, novel approaches have been proposed to understand many physiological and agronomical traits in crop plants (Chen et al ., ; Gramazio et al ., ; Prince et al., ; Shankar et al ., ; Wang et al ., ; Zhang et al ., ,b).…”

The growths of leaves, shoots, roots and reproductive organs partly share their genetic control in maize plants

“…) and potato (Anithakumari et al . ), and for leaf and silk growths in mapping population of maize (Welcker et al . ).…”

Genetic diversity of potato for nitrogen use efficiency under low input conditions in Ethiopia

“…Additional QTLs for DTM and PH under both N conditions, Vmax, AUC and TYPP under high N conditions, and UCC under low N condition (in total about 11 QTLs) were co-located between 38-56cM on linkage group V. Previously QTLs associated with foliage traits were also identified in this region: QTLs for fresh biomass (Anithakumari et al, 2011), plant height, shoot fresh weight and shoot dry weight under drought stress and recovery condition (Anithakumari et al, 2012), for fresh and dry harvest index and stem diameter under drought and well-watered conditions (Khan et al, 2014) were identified in this region. Most of the QTLs detected in this region are more than 20cM downstream of the CDF1 gene, and may constitute different loci, independent of the earliness locus.…”

“…QTL analysis with a wide range of molecular markers provides opportunities not only for the identification of QTLs that determine the phenotypic value of a particular trait, but also for the analysis of the relationships between traits (Lebreton et al, 1995;Simko et al, 1997). In the last two decades many QTL analysis studies have been published on different traits of potato, such as flower color, foliage maturity, tuber skin texture, dry matter content, specific gravity and yield (McCord et al,2011), yield, agronomic and quality traits (Bradshaw et al,2008), tuber yield and starch content (Schafer-Pregl et al,1998, Werij et al, 2012, tuber dormancy (van den , tuber shape (Van Eck et al, 1994b), tuber skin color (Gebhardt et al,1989), tuber flesh color (Bonierbale et al, 1988), shoot fresh weight, tuber number, tuber weight and root length under drought stress and recovery conditions (Anithakumari et al, 2011;2012) and NUE related canopy cover traits under contrasting N regimes (Ospina, 2016). However, knowledge about the genetic dissection of NUE in potato is still limited and hardly any QTL has been published for NUE and NUE related traits of potato.…”

“…In the last two decades many QTL analysis studies have been published on different traits of potato, such as flower colour, foliage maturity, tuber skin texture, dry matter content, specific gravity and yield (McCord et al, 2011), yield, agronomic and quality traits (Bradshaw et al, 2008), tuber yield and starch content (Schafer-Pregl et al, 1998), tuber dormancy (van den , tuber shape (Van Eck et al, 1994), tuber skin colour (Gebhardt et al, 1989), tuber flesh colour (Bonierbale et al, 1988) and drought related traits (Anithakumari et al, 2011(Anithakumari et al, , 2012Khan et al, 2014) .The number of QTL studies for NUE are still very limited.…”